Motor controller

ABSTRACT

A motor controller, comprising a first simulation control unit ( 8 ) and a second simulation control unit ( 9 ) as a feed forward control means for inputting a command to an actual control unit ( 10 ) performing a feedback control, wherein the control parameter of the first simulation control unit ( 8 ) is set so that the high-speed property of a control response is increased, and the control parameter of the second simulation control unit ( 9 ) is set so that the stability of the control response is increased, whereby an entire feed forward control means can be designed so as to meet the requirements for the high-speed property and high stability of the control response.

TECHNICAL FIELD

[0001] The present invention relates to a motor controller for an electric motor such as a direct-current motor, an induction motor, a synchronous motor, a linear motor or the like for driving a load mechanism such as a table or an arm of a robot in a machine tool.

BACKGROUND ART

[0002] As a controller for controlling a machine system comprised of a load mechanism such as a table or an arm of a robot in a machine tool, a driving device such as a direct-current motor, an induction motor, a synchronous motor, a linear motor or the like, and a transmission mechanism for connecting the load mechanism with the driving device, a controller having two degrees of freedom is often used, which has a feedback control unit which relies on a command value and an output value of a machine system to perform the control, and a feed forward control unit which relies only on the command value to perform the control. For example, Japanese Patent Application Laid Open No. 06-030578 discloses an exemplary controller having two degrees of freedom.

[0003]FIG. 1 is a block diagram illustrating the configuration of a conventional motor controller. The motor controller in FIG. 1 comprises feed forward signal processing circuit 25 and B control circuit 23 for performing a feedback control, and is a controller having two degrees of freedom for controlling machine system 6 which comprises load mechanism 1, transmission mechanism 2, electric motor 3, power converting circuit 4, and actual observing unit 5.

[0004] Power converting circuit 4 drives electric motor 3 in response to torque command T applied thereto, and a rotating force of electric motor 3 is transmitted to load mechanism 1 through transmission mechanism 2, thereby operating load mechanism 1. Actual observing unit 5 is rotation detector 4 for detecting a rotational speed ω and a rotation angle θ of electric motor 3.

[0005] Feed forward signal processing circuit 25 comprises two-inertia-system simulation circuit 24 in which a system is built through approximation and modeling of machine system 6, and A control circuit 22 which is intended to control this two-inertia-system simulation circuit 24. Two-inertia-system simulation circuit 24 receives torque signal T_(Mr) applied from the A control circuit, and performs predetermined functional operations including at least two integrations to provide simulation rotation angle signal θ_(Mr) and simulation speed signal ω_(Mr). A control circuit 22 generates simulation torque signal T_(Mr) applied to two-inertia-system simulation circuit 24 based on commanded rotation angle signal ω_(ref) provided from command generator 7 as well as simulation rotation angle signal θ_(Mr) and simulation speed signal ω_(Mr) provided from two-inertia-system simulation circuit 24.

[0006] B control circuit 23 comprises a position control circuit (not shown) and a speed control circuit (not shown). The position control circuit calculates and provides a speed command based on a deviation of simulation rotation angle signal θ_(Mr) from actual rotation angle signal θ detected by actual observing unit 5, while the speed control circuit calculates torque command T based on a deviation of the speed command provided from the position control circuit from actual speed signal ω, and provides torque command T to power converting circuit 4. B control circuit 23 can achieve high speed position control performance with the provision of the position control circuit and speed control circuit as mentioned.

[0007] Generally, in a motor controller as described above, the control response varies in high-speed property and stability depending on control parameters set in A control circuit 22, two-inertia-system simulation circuit 24 and the like. Generally, in such a motor controller, the parameters are relatively readily set for its control system when the high-speed property is solely required for the control response, or when the stability is solely required for the control response. Typically, however, such a motor controller is often required to provide both the high-speed property and high stability of the control response. In this event, the control parameters of A control circuit 22 and two-inertia-system simulation circuit 24 must be set to meet the requirements for both the high-speed property and high stability of the control response.

[0008] However, such a motor controller implies a problem in that adjustments of the control parameters to meet the requirements for both the high-speed property and high stability for the control response are very difficult and time-consuming work for an operator.

[0009] Particularly, in failure of establishment of conditions under which a machine system such as machine system 6 is regarded as an ideal rigid body, for example, when machine system 6 appears to include spring characteristics, two-inertia-system simulation circuit 24, which models machine system 6, is subjected to a fourth or higher order control, so that the motor control must find roots of a quartic equation in order to adjust control parameters of A control circuit 22 and two-inertia-system circuit 24 that meet the requirements for both the high-speed property and high stability of the control response, causing a problem in that the adjustments of these control parameters are made difficult and time-consuming.

[0010] As described above, in the motor controller, the control response varies in the high-speed property and stability depending on the control parameters set in control circuits. Generally, in such a motor controller, the control parameters are relatively readily set for its control system when the high-speed property is solely required for the control response, or when the stability is solely required for the control response. Typically, however, such a motor controller is often required to provide both the high-speed property and high stability of the control response. In this event, the control parameters of control circuits must be set to meet the requirements for both the high-speed property and high stability of the control response. However, the conventional motor controller implies a problem in that adjustments of the control parameters to meet the requirements for both the high-speed property and high stability of the control response are very difficult and time-consuming works for the operator.

DISCLOSURE OF THE INVENTION

[0011] It is an object of the present invention to provide a motor controller which is capable of readily realizing both of the high-speed property and high stability of a control response.

[0012] To achieve the above object, a motor controller according to the present invention includes two components: first simulation control means and second simulation control means as feed forward control means for applying a command to an actual control unit for performing a feedback control. By doing so, the overall feed forward control means can be designed to meet the requirements for the high-speed property and high stability of a control response by setting a control parameter of the first simulation control means to increase the high-speed property of the control response and setting a control parameter of the second simulation control means to increase the stability of the control response. While it is easy to set the control parameter of each simulation control means to meet the requirement for either the high-speed property or high stability of the control response, the motor controller according to the present invention can readily realize both the high-speed property and high stability of the control response.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013]FIG. 1 is a block diagram illustrating the configuration of a conventional motor controller;

[0014]FIG. 2 is a block diagram illustrating the configuration of a motor controller according to a first embodiment of the present invention;

[0015]FIG. 3 is a block diagram illustrating the configuration of first simulation control unit 28 in a motor controller according to a second embodiment of the present invention;

[0016]FIG. 4 is a block diagram illustrating the configuration of first simulation control unit 38 in a motor controller according to a third embodiment of the present invention;

[0017]FIG. 5 is a block diagram illustrating the configuration of first simulation control unit 48 in a motor controller according to a fourth embodiment of the present invention;

[0018]FIG. 6 is a block diagram illustrating the configuration of first simulation control unit 58 in a motor controller according to a fifth embodiment of the present invention;

[0019]FIG. 7 is a block diagram illustrating the configuration of first simulation controller 68 a in a motor controller according to a sixth embodiment of the present invention;

[0020]FIG. 8 is a block diagram illustrating the configuration of first simulation controller 78 a in a motor controller according to a seventh embodiment of the present invention;

[0021]FIG. 9 is a block diagram illustrating the configuration of first simulation controllers 88 a, 98 a in a motor controller according to an eighth embodiment of the present invention;

[0022]FIG. 10 is a block diagram illustrating the configuration of first simulation position control unit 8 a 12 in a motor controller according to a ninth embodiment of the present invention;

[0023]FIG. 11 is a block diagram illustrating the configuration of first simulation speed control unit 8 a 22 in a motor controller according to a tenth embodiment of the present invention;

[0024]FIG. 12 is a block diagram illustrating the configuration of first simulation position control unit 8 a 32 in a motor controller according to an eleventh embodiment of the present invention;

[0025]FIG. 13 is a block diagram illustrating the configuration of first simulation speed control unit 8 a 4 in a motor controller according to a twelfth embodiment of the present invention;

[0026]FIG. 14 is a block diagram illustrating a first numerical model 138 b in a motor controller according to a thirteenth embodiment of the present invention;

[0027]FIG. 15 is a block diagram illustrating a first numerical model 148 i in a motor controller according to a fourteenth embodiment of the present invention;

[0028]FIG. 16 is a block diagram illustrating the configuration of second simulation control unit 19 in a motor controller according to a fifteenth embodiment of the present invention;

[0029]FIG. 17 is a block diagram illustrating the configuration of second simulation control unit 29 in a motor controller according to a sixteenth embodiment of the present invention;

[0030]FIG. 18 is a block diagram illustrating second numerical model 179 b in a motor controller according to a seventeenth embodiment of the present invention;

[0031]FIG. 19 is a block diagram illustrating a second simulation controller 19 a in a motor controller according to an eighteenth embodiment of the present invention;

[0032]FIG. 20 is a block diagram illustrating second simulation controller 29 a in a motor controller according to a nineteenth embodiment of the present invention;

[0033]FIG. 21 is a block diagram illustrating second simulation controller 19 c in a motor controller according to a twentieth embodiment of the present invention;

[0034]FIG. 22 is a block diagram illustrating second simulation control unit 39 in a motor controller according to a twenty first embodiment of the present invention;

[0035]FIG. 23 is a block diagram illustrating the configuration of second simulation controller 19 d in a motor controller according to a twenty second embodiment of the present invention;

[0036]FIG. 24 is a block diagram illustrating the configuration of second simulation position control unit 9 d 2;

[0037]FIG. 25 is a block diagram illustrating the configuration of second simulation speed control unit 9 d 6;

[0038]FIG. 26 is a block diagram illustrating the configuration of second simulation torsional position compensator 9 d 10;

[0039]FIG. 27 is a block diagram illustrating the configuration of second simulation torsional speed compensator 9 d 8;

[0040]FIG. 28 is a block diagram illustrating the configuration of second simulation controller 29 d in a motor controller according to a twenty third embodiment of the present invention;

[0041]FIG. 29 is a block diagram illustrating the configuration of second numerical model 19 e in a motor controller according to a twenty fourth embodiment of the present invention;

[0042]FIG. 30 is a block diagram illustrating the configuration of spring numerical model 9 e 2;

[0043]FIG. 31 is a block diagram illustrating the configuration of actual control unit 10 in a motor controller according to a twenty fifth embodiment of the present invention;

[0044]FIG. 32 is a block diagram illustrating the configuration of actual control unit 11 in a motor controller according to a twenty sixth embodiment of the present invention;

[0045]FIG. 33 is a block diagram illustrating the configuration of actual control unit 12 in a motor controller according to a twenty seventh embodiment of the present invention;

[0046]FIG. 34 is a block diagram illustrating the configuration of a motor controller according to a twenty eighth embodiment of the present invention;

[0047]FIG. 35 is a graph showing the result of a simulation in the motor controller according to the twenty eighth embodiment of the present invention;

[0048]FIG. 36 is a block diagram illustrating the configuration of a motor controller according to a twenty ninth embodiment of the present invention;

[0049]FIG. 37 is a graph showing the result of a simulation in the motor controller according to the twenty ninth embodiment of the present invention; and

[0050]FIG. 38 is a block diagram illustrating the configuration of a motor controller according to a thirtieth embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

[0051] First Embodiment

[0052] First, description will be made on a motor controller according to a first embodiment of the present invention. FIG. 2 is a block diagram illustrating the configuration of the motor controller according to this embodiment.

[0053] As illustrated in FIG. 2, the motor controller according to this embodiment is an apparatus for controlling the operation of machine system 6 based on commanded rotation angle signal θ_(ref) provided from command generator 7, and comprises first simulation control unit 8, second simulation control unit 9, and actual control unit 10.

[0054] First simulation control unit 8 receives commanded rotation angle signal θ_(ref) provided from command generator 7, calculates first simulation position signal θ_(m1,) first simulation speed signal ω_(m1) and first simulation acceleration signal α_(m1) based on commanded rotation angle signal θ_(ref) and a first control parameter, and provides the calculated signals. First simulation control unit 9 calculates first simulation position signal θ_(m1) first simulation speed signal ω_(m1) and first simulation acceleration signal α_(m1) as expressed by the following equations (1)-(3):

θ_(m1)=1/(T ₁ ×s+1)²×θ_(ref)   (1)

ω_(m1) =s/(T ₁ ×s+1)²×θ_(ref)   (2)

α_(m1) =s ²/(T ₁ ×s+1)²×θ_(ref)   (3)

[0055] where T₁ is a time constant which is the first control parameter, and s is a differential operator.

[0056] Second simulation control unit 9 calculates second simulation position signal θ_(m2), second simulation speed signal ω_(m2), second simulation acceleration signal a α_(m2), and simulation torque signal T_(m2) based on first simulation position signal θ_(m1), first simulation speed signal ω_(m1), first simulation acceleration signal α_(m1), and a second control parameter, and provides the calculated signals.

[0057] Second simulation control unit 9 calculates second simulation position signal θ_(m2), second simulation speed signal ω_(m2), second simulation acceleration signal α_(m2), and simulation torque signal T_(m2) as expressed by the following equations (4)-(6):

θ_(m2)=θ_(m1)/(T ₂ ×s+1)   (4)

ω_(m2)=ω_(m1)/(T ₂ ×s+1)   (5)

α_(m2)=α_(m1)/(T ₂ ×s+1)   (6)

T _(m2)=α_(m2) ×J   (7)

[0058] where T₂ is a time constant which is the second control parameter, s is a differential operator, and J is the inertia of machine system 6.

[0059] Actual control unit 10 receives second simulation position signal θ_(m2), second simulation speed signal ω_(m2), second simulation acceleration signal α_(m2) and simulation torque signal T_(m2) for performing a feedback control to calculate and provide torque command T.

[0060] The motor controller according to this embodiment comprises a pair of first simulation control unit 8 and second simulation control unit 9 as feed forward control means which applies a command to actual control unit 10 for performing the feedback control. By doing so, the control parameter of first simulation control unit 8 is set to improve the high-speed property of the control response, while the control parameter of second simulation control unit 9 is set to increase the stability of the control response, thereby making it possible to allow the design of the overall feed forward control means to meet the requirements for the high-speed property and high stability of the control response. Since it is easy to set the control parameters of respective simulation control units 8, 9 to meet the requirement for either the high-speed property or high stability of the control response, the motor controller according to this embodiment can readily realize both the high-speed property and high responsibility of the control response.

[0061] In addition, the motor controller according to this embodiment can generate smooth second simulation position signal θ_(m2), second simulation speed signal ω_(m2) and second simulation acceleration signal α_(m2), which are applied to actual control unit 10, even if command generator 7 provides a discontinuous commanded rotation angle signal.

[0062] Second Embodiment

[0063] Next, description will be made on a motor controller according to a second embodiment of the present invention. This embodiment and third through fourteenth embodiments illustrate embodiments of first simulation control means in the motor controller according to the present invention, and in the motor controller according to this embodiment, those illustrated in fifteenth through twenty seventh embodiments are applied to second simulation control means, actual control means, and the like.

[0064] The motor controller according to this embodiment differs from the motor controller in FIG. 2 in that first simulation control unit 28 is provided instead of first simulation control unit 8. FIG. 3 is a block diagram illustrating the configuration of first simulation control unit 28 in the motor controller according to this embodiment. As illustrated in FIG. 3, first simulation control unit 28 comprises first simulation controller 8 a and first numerical model 8 b.

[0065] First simulation controller 8 a receives commanded rotation angle signal θ_(ref), first simulation position signal θ_(m1) and first simulation speed signal ω_(m1), and provides first simulation torque signal T_(m1). First numerical model 8 b receives first simulation torque signal T_(m1) provided from first simulation controller 8 a, and provides first simulation position signal θ_(m1), first simulation speed signal ω_(m1) and first simulation acceleration signal α_(m1).

[0066] First simulation controller 8 a calculates first simulation torque signal T_(m1) as expressed by the following equation (8):

T _(m1) =J _(m1) ×{K ₁×(θ_(ref)−θ_(m1))−K ₂×ω_(m1)}  (8)

[0067] where J_(m1) represents the inertia of first numerical model 8 b, and K₁, K₂ represent control gains.

[0068] First numerical model 8 b in turn calculates first simulation acceleration signal α_(m1) by dividing inertia J_(m1) by first simulation torque signal T_(m1), first simulation speed signal ω_(m1) by integrating first simulation acceleration signal α_(m1), and first simulation position signal θ_(m1) by integrating first simulation speed signal ω_(m1). In other words, first simulation position signal θ_(m1), first simulation speed signal ω_(m1) and first simulation acceleration signal α_(m1) are calculated as expressed by the following equations (9)-(11):

α_(m1) =T _(m1) /J _(m1)   (9)

ω_(m1)=α_(m1) /s   (10)

θ_(m1)=ω_(m1) /s   (11)

[0069] The motor controller according to this embodiment provides smooth first simulation acceleration signal α_(m1) by forming first simulation control unit 28 of first simulation controller 8 a and first numerical model 8 b, and simultaneously can speed up the response characteristic of first simulation position signal θ_(m1) to commanded rotation angle signal θ_(ref) because first simulation controller 8 a performs the feedback control to reduce an error of first simulation position signal θ_(m1) with respect to commanded rotation angle signal θ_(ref).

[0070] Third Embodiment

[0071] Next, detailed description will be made on a motor controller according to a third embodiment of the present invention. The motor controller according to this embodiment differs from the motor controller of FIG. 2 in that first simulation control unit 38 is provided instead of first simulation control unit 8. FIG. 4 is a block diagram illustrating the configuration of first simulation control unit 38. As illustrated in FIG. 4, first simulation control unit 38 comprises first command processor 8 c, first simulation signal processor 8 d, and second simulation signal processor 8 e.

[0072] First command processor 8 c receives commanded rotation angle signal θ_(ref) and calculates first simulation speed signal ω_(m1) through the calculation of the aforementioned equation (2), and provides first simulation speed signal ω_(m1). First simulation signal processor 8 d integrates the value of first simulation speed signal ω_(m1), and provides the integrated value signal as first simulation position signal θ_(m1). Second simulation signal processor 8 e differentiates the value of first simulation speed signal ω_(m1), and provides the differentiated value signal as first simulation acceleration signal α_(m1).

[0073] The motor controller according to this embodiment can calculate first simulation position signal θ_(m1), first simulation speed signal ω_(m1) and first simulation acceleration signal α_(m1) with a less amount of processing, as compared with the motor controller according to the second embodiment.

[0074] Fourth Embodiment

[0075] Next, detailed description will be made on a motor controller according to a fourth embodiment of the present invention. The motor controller according to this embodiment differs from the motor controller of FIG. 2 in that first simulation control unit 48 is provided instead of first simulation control unit 8.

[0076]FIG. 5 is a block diagram illustrating the configuration of first simulation control unit 48. As illustrated in FIG. 5, first simulation control unit 48 comprises second command processor 8 f, third simulation signal processor 8 g, and fourth simulation signal processor 8 h.

[0077] Second command processor 8 f receives commanded rotation angle signal θ_(ref), calculates first simulation position signal θ_(m1) through the aforementioned equation (1), and provides the calculated signal. Third simulation signal processor 8 g differentiates first simulation position signal θ_(m1) to provide first simulation speed signal ω_(m1). Fourth simulation signal processor 8 h differentiates first simulation speed signal ω_(m1) to provide first simulation acceleration signal α_(m1).

[0078] The motor controller according to this embodiment can generate first simulation position signal θ_(m1), first simulation speed signal ω_(m1) and first simulation acceleration signal α_(m1) with a less amount of processing, as compared with the motor controller according to the second embodiment, and can reduce the error of first simulation position signal θ_(m1) with respect to commanded rotation angle signal θ_(ref) in a steady state from the motor controller according to the second embodiment because first simulation control unit 48 does not include a feedback element.

[0079] Fifth Embodiment

[0080]FIG. 6 is a block diagram illustrating first simulation control unit 58 in a motor controller according to this embodiment. The motor controller according to this embodiment differs from the motor controller of FIG. 2 in that first simulation control unit 58 is provided instead of first simulation control unit 8.

[0081] As illustrated in FIG. 6, first simulation control unit 58 comprises first numerical model 8 i and fifth simulation signal processor 8 j in addition to first simulation controller 8 a in first simulation control unit 28 of FIG. 3.

[0082] First numerical model 8 i receives first simulation torque signal T_(m1), divides first simulation torque signal T_(m1) by inertia J_(m1), integrates the result, as shown in the following equation (12), which is provided as first simulation speed signal ω_(m1), and integrates first simulation speed signal ω_(m1) as shown in the following equation (13) and provides the integrated signal as first simulation position signal θ_(m1).

ω_(m1) =T _(m1)/(s×J _(m1))   (12)

θ_(m1)=ω_(m1) /s   (13)

[0083] Fifth simulation signal processor 8 j differentiates an output value of a first-order filter, which receives first simulation speed signal ω_(m1), as shown in the following equation (14), and provides the differentiated value as first simulation acceleration signal α_(m1).

α_(m1) =s×ω _(m1)/(T ₃ ×s+1)   (14)

[0084] where T₃ is the time constant of the first-order filter.

[0085] The motor controller according to the present invention can adjust the amplitude and phase of first simulation acceleration signal α_(m1) with the provision of fifth simulation signal processor 8 j.

[0086] Sixth Embodiment

[0087] Next, detailed description will be made on a motor controller according to a sixth embodiment of the present invention. While the motor controller according to this embodiment is substantially similar to first simulation control unit 28 of FIG. 3 and first simulation control unit 58 of FIG. 6 in the configuration of the first simulation control unit, it differs from first simulation control units 28, 58 in that first simulation controller 68 a is provided instead of first simulation controller 8 a.

[0088]FIG. 7 is a block diagram illustrating the configuration of first simulation controller 68 a in the motor controller according to this embodiment. As illustrated in FIG. 7, first simulation controller 68 a comprises first simulation position control unit 8 a1 and first simulation speed control unit 8 a 2.

[0089] First simulation position control unit 8 a 1 receives commanded rotation angle signal θ_(ref) and first simulation position signal θ_(m1), and solves the following equation (15) to calculate and provide first simulation speed command signal ω_(ref):

ω_(ref) =K _(P1)×(θ_(ref)−θ_(m1))   (15)

[0090] where K_(P1) is a position proportional control gain.

[0091] First simulation speed control unit 8 a 2 receives first simulation speed command signal ω_(ref) and first simulation speed signal ω_(m1), and solves the following equation (16) to calculate and output first simulation torque signal T_(m1):

T _(m1) =K _(V1)×(ω_(ref)−ω_(m1))   (16)

[0092] where K_(V1)is a speed proportional control gain.

[0093] With the first simulation controller comprised of the first simulation position control unit and first simulation speed control unit, the motor controller according to this embodiment can achieve similar response characteristics to the motor controllers according to the second and fifth embodiments even if the first simulation position control unit has a gain smaller than control gains K₁, K₂ of the second and fifth motor controllers.

[0094] Seventh Embodiment

[0095] Next, detailed description will be made on a motor controller according to a seventh embodiment of the present invention.

[0096] The motor controller according to this embodiment differs from the motor controller according to the sixth embodiment in that first simulation controller 78 a is provided instead of first simulation controller 68 a.

[0097]FIG. 8 is a block diagram illustrating first simulation controller 78 a. As illustrated in FIG. 8, first simulation controller 78 a comprises first simulation position control unit 8 a 3, first simulation speed control unit 8 a 4, and adder 8 a 5.

[0098] First simulation position control unit 8 a 3 receives commanded rotation angle signal θ_(ref) and first simulation position signal θ_(m1), and solves the following equation (17) to provide first simulation torque command signal Tx_(m1):

Tx _(m1) =K _(P1)×(θ_(ref)−θ_(m1))   (17)

[0099] where K_(P1) is a position proportional control gain.

[0100] First simulation speed control unit 8 a 4 receives commanded rotation angle signal θ_(ref) and first simulation speed signal ω_(m1), and solves-the following equation (18) to provide second simulation torque command signal Tv_(m1):

Tv _(m1) =K _(V1)×(θ_(ref) /s−ω _(m1))   (18)

[0101] where K_(V1) is a speed proportional control gain.

[0102] Adder 8 a 5 adds first simulation torque command signal Tx_(m1) and second simulation torque command signal Tv_(m1), and provides the sum signal as first simulation torque signal T_(m1).

[0103] The motor controller according to this embodiment can switch a position control mode and a speed control mode because first simulation position control unit 8 a 3, which is a position controller, is arranged in parallel with first simulation speed control unit 8 a 4 which is a speed controller.

[0104] Eighth Embodiment

[0105] Next, detailed description will be made on a motor controller according to an eighth embodiment of the present invention. The motor controller according to this embodiment is substantially similar in the configuration to the motor controllers according to the sixth and seventh embodiments, and differs from the sixth and seventh embodiments in that first simulation controllers 88 a, 98 a illustrated in FIGS. 9(a) and 9(b) are provided instead of first simulation controllers 68 a, 78 a in FIGS. 7 and 8.

[0106]FIG. 9(a) is a block diagram illustrating the configuration of first simulation controller 88 a, and FIG. 9(b) is a block diagram illustrating the configuration of first simulation controller 98 a.

[0107] As illustrated in FIGS. 9(a) and 9(b), first simulation controllers 88 a, 98 a differ from first simulation controllers 68 a, 78 a in FIGS. 7 and 8 in that first simulation limiter 8 a 6 and first simulation limiter 8 a 7 are provided, respectively.

[0108] First simulation limiter 8 a 6 and first simulation limiter 8 a 7 limit the value of first simulation torque signal T_(m1) such that first simulation torque signal T_(m1) falls within a predetermined torque range of electric motor 3. With the addition of such simulation limiters 8 a 6, 8 a 7, the motor controller according to this embodiment can previously generate first simulation torque signal T_(m1) in consideration of a maximum driving torque of the electric motor.

[0109] Ninth Embodiment

[0110] Next, detailed description will be made on a motor controller according to a ninth embodiment of the present invention.

[0111] The motor controller according to this embodiment comprises first simulation position control unit 8 a 12 instead of first simulation position control unit 8 a 1 of first simulation controllers 68 a, 88 a in FIGS. 7 and 9.

[0112]FIG. 10 is a block diagram illustrating the configuration of first simulation position control unit 8 a 12. As illustrated in FIG. 10, first simulation position control unit 8 a 12 comprises subtractor 8 a 1 a, coefficient multiplier 8 a 1 b, coefficient multiplier 8 a 1 c, integrator 8 a 1 d, and adder 8 a 1 e.

[0113] Subtractor 8 a 1 a subtracts first simulation position signal θ_(m1) from commanded rotation angle signal θ_(ref) to provide first simulation position error signal Ex_(m1).

[0114] Coefficient multiplier 8 a 1 b multiplies first simulation position error signal Ex_(m1) by K_(P1), and provides the product signal as tenth simulation signal SI10. Coefficient multiplier 8 a 1 c multiplies first simulation position error signal Ex_(m1) by K_(I1), and provides the product signal as eleventh simulation signal SI11. Integrator 8 a 1 d integrates the eleventh simulation signal, and provides the integrated value as twelfth simulation signal SI12.

[0115] Adder 8 a 1 e adds tenth simulation signal SI10 and twelfth simulation signal SI12, and provides the sum signal as first simulation speed command signal ω_(ref).

[0116] Since integrator 8 a 1 d is added to first simulation position control unit 8 a 12 to perform a proportional and integral control, the motor controller according to this embodiment can eliminate an error between first simulation position signal θ_(m1) and commanded rotation angle signal θ_(ref) even if a processing error exists.

[0117] Tenth Embodiment

[0118] Next, a motor controller according to a tenth embodiment of the present invention will be described in detail with reference to FIG. 11. The motor controller according to this embodiment comprises first simulation speed control unit 8 a 22 instead of first simulation speed control unit 8 a1 in first simulation controllers 68 a, 88 a of FIGS. 7 and 9.

[0119]FIG. 11 is a block diagram illustrating the configuration of first simulation speed control unit 8 a 22. As illustrated in FIG. 11, first simulation speed control unit 8 a 22 comprises subtractor 8 a 2 a, coefficient multiplier 8 a 2 b, coefficient multiplier 8 a 2 c, integrator 8 a 2 d, and adder 8 a 2 e.

[0120] Subtractor 8 a 2 a subtracts first simulation speed signal ω_(m1) from first simulation speed command signal ω_(ref), and provides the difference value as first simulation position error signal Ev_(m1).

[0121] Coefficient multiplier 8 a 2 b multiplies first simulation speed error signal Ev_(m1) by K_(V1), and provides the product value as thirteenth simulation signal SI13, while coefficient multiplier 8 a 2 c multiplies first simulation speed error signal Ev_(m1) by K_(I1), and provides the product value as fourteenth simulation signal SI14.

[0122] Integrator 8 a 2 d integrates fourteenth simulation signal SI14, and provides the integrated value as fifteenth simulation signal SI15.

[0123] Adder 8 a 2 e adds thirteenth simulation signal SI13 and fifteenth simulation signal SI15, and provides the sum signal as first simulation torque command signal T_(m1a).

[0124] With the addition of integrator 8 a 2 d to first simulation speed control unit 8 a 22, a proportional and integral control is performed even when a position control mode is switched to a speed control mode and vice versa, so that the motor controller according to this embodiment can eliminate an error between first simulation position signal θ_(m1) and commanded rotation angle signal θ_(ref) in a steady state.

[0125] Eleventh Embodiment

[0126] Next, detailed description will be made on a motor controller according to an eleventh embodiment of the present invention. The motor controller according to this embodiment comprises first simulation speed control unit 8 a 32 instead of first simulation speed control unit 8 a 3 of first simulation controllers 78 a, 98 a in FIGS. 8 and 9.

[0127]FIG. 12 is a block diagram illustrating the configuration of first simulation position control unit 8 a 32. As illustrated in FIG. 12, first simulation position control unit 8 a 32 comprises subtractor 8 a 3 a, coefficient multiplier 8 a 3 b, coefficient multiplier 8 a 3 c, integrator 8 a 3 d, and adder 8 a 3 e.

[0128] Subtractor 8 a 3 a subtracts first simulation position signal θ_(m1) from commanded rotation angle signal θ_(ref), and provides the difference value as first simulation position error signal Ex_(m1). Coefficient multiplier 8 a 3 b multiplies first simulation position error signal Ex_(m1) by K_(P1), and provides the product signal as sixteenth simulation signal SI16. Coefficient multiplier 8 a 3 c multiplies first simulation position error signal Ex_(m1) by K_(I1), and provides the product signal as seventeenth simulation signal SI17. Integrator 8 a 3 d integrates seventeenth simulation signal SI17, and provides the integrated signal as eighteenth simulation signal SI18.

[0129] Adder 8 a 3 e adds sixteenth simulation signal SI16 and eighteenth simulation signal SI18, and provides- the sum signal as first simulation torque command signal Tx_(m1).

[0130] Since integrator 8 a 3 d is added to first simulation position control unit 8 a 32 to perform a proportional and integral control, the motor controller according to this embodiment can eliminate an error between first simulation position signal θ_(m1) and commanded rotation angle signal θ_(ref) even if a calculation error exists.

[0131] Twelfth Embodiment

[0132] Next, detailed description will be made on a motor controller according to a twelfth embodiment of the present invention. The motor controller according to this embodiment comprises first simulation speed control unit 8 a 42 instead of first simulation speed control unit 8 a 4 of first simulation controllers 78 a, 98 a in FIGS. 8 and 9.

[0133]FIG. 13 is a block diagram illustrating the configuration of first simulation speed control unit 8 a 42. As illustrated in FIG. 13, first simulation speed control unit 8 a 42 comprises differentiator 8 a 4 a, subtractor 8 a 4 b, coefficient multiplier 8 a 4 c, coefficient multiplier 8 a 4 f, integrator 8 a 4 d, and adder 8 a 4 e.

[0134] Differentiator 8 a 4 a differentiates commanded rotation angle signal θ_(ref) to provide nineteenth simulation signal SI19. Subtractor 8 a 4 b subtracts nineteenth simulation signal SI19 from first simulation speed signal ω_(m1) to provide first simulation speed error signal Ev_(m1). Coefficient multiplier 8 a 4 c multiplies first simulation speed error signal Ev_(m1) by K_(I1), and provides the product signal as twentieth simulation signal SI20. Coefficient multiplier 8 a 4 f multiplies the value of first simulation speed error signal Ev_(m1) by K_(v1), and provides the product signal as twenty first simulation signal SI21. Integrator 8 a 4 d integrates twentieth simulation signal SI20 to provide twenty second simulation signal SI22. Adder 8 a 4 e adds twenty first simulation signal SI21 and twenty second simulation signal SI22 to provide second simulation torque command signal Tv_(m1).

[0135] Since first simulation speed control unit 8 a 42 comprises integrator 8 a 4 d to perform a proportional and integral control, the motor controller according to this embodiment can eliminate an error between first simulation position signal θ_(m1) and commanded rotation angle signal θ_(ref) in a steady state even if the position control mode is switched to the speed control mode and vice versa.

[0136] Thirteenth Embodiment

[0137] Next, detailed description will be made on a motor controller according to a thirteenth embodiment of the present invention.

[0138] The motor controller according to this embodiment comprises first numerical model 138 b instead of first model 8 b in first simulation control unit 28 of FIG. 3.

[0139]FIG. 14 is a block diagram illustrating the configuration of first numerical model 138 b. As illustrated in FIG. 14, first numerical model 138 b comprises coefficient multiplier 8 b 1, integrator 8 b 2, and integrator 8 b 3.

[0140] Coefficient multiplier 8 b 1 receives first simulation torque signal T_(m1), calculates first simulation acceleration signal α_(m1) as expressed by the following equation (19), and provides first simulation acceleration signal α_(m1). Integrator 8 b 2 integrates first simulation acceleration signal α_(m1) as expressed by the following equation (20), and provides the integrated signal as first simulation speed signal ω_(m1). Integrator 8 b 3 integrates first simulation speed signal ω_(m1) as expressed by the following equation (21), and provides the integrated value as first simulation position signal θ_(m1).

α_(m1) =T _(m1) /J   (19)

ω_(m1)=α_(m1) /s   (20)

θ_(m1)=θ_(m1) /s   (21)

[0141] Like the motor controller according to the second embodiment, by fixing first numerical model 138 b to a rigid body model, the motor controller according to this embodiment can readily set control parameters such as control gains K₁, K₂, and the like of first simulation controllers 8 a, 68 a, 78 a, 88 a, 98 a in accordance with required response characteristics.

[0142] Fourteenth Embodiment

[0143] Next, detailed description will be made on a motor controller according to a fourteenth embodiment of the present invention.

[0144] The motor controller according to this embodiment comprises first numerical model 148 i instead of first numerical model 8 i in first simulation control unit 58 of FIG. 6.

[0145]FIG. 15 is a block diagram illustrating the configuration of first numerical model 148 i. As illustrated in FIG. 15, first numerical model 8 i comprises coefficient multiplier 8 i 1, integrator 8 i 2, and integrator 8 i 3.

[0146] Coefficient multiplier 8 i 1 receives first simulation torque signal T_(m1), and provides sixteenth simulation signal SI16 as expressed by the aforementioned equation (19). Integrator 8 i 2 integrates sixteenth simulation signal SI16 to provide first simulation speed signal ω_(m1). Integrator 8 i 3 integrates first simulation speed signal ω_(m1) to provide first simulation position signal θ_(m1).

[0147] By fixing first numerical model 148 i to a rigid body model in a manner similar to first numerical model 8 i, the motor controller according to this embodiment can readily set control parameters such as control gains K₁, K₂, and the like of the first simulation controllers in accordance with required response characteristics.

[0148] Fifteenth Embodiment

[0149] Next, detailed description will be made on a motor controller according to a fifteenth embodiment of the present invention. This embodiment and sixteenth through twenty fourth embodiments illustrate embodiments of second simulation control means in the motor controller according to the present invention, and in the motor controller according to this embodiment, those illustrated in the first through fourteenth and twenty fifth through twenty seventh embodiments are applied to the first simulation control means, actual control means, and the like.

[0150]FIG. 16 is a block diagram illustrating the configuration of second simulation control unit 19. As illustrated in FIG. 16, second simulation control unit 19 comprises second simulation controller 9 a and second numerical model 9 b.

[0151] Second simulation controller 9 a receives first simulation position signal θ_(m1), first simulation speed signal ω_(m1), first simulation acceleration signal α_(m1), second simulation position signal θ_(m2), and second simulation speed signal ω_(m2), calculates second simulation torque signal T_(m2) in accordance with the following equation (22), and provides the calculated signal:

T _(m2) =J _(m2)×α_(m1) ×J _(m3) ×{K ₃(θ_(m1)−θ_(m2))−K ₄(ω_(m1)−ω_(m2))}  (22)

[0152] where J_(m2), J_(m3) represent the inertia of the second numerical model, and K₃, K₄ represent control gains.

[0153] Second numerical model 9 b receives second simulation torque signal T_(m2), calculates second simulation position signal θ_(m2), second simulation speed signal ω_(m2), and second simulation acceleration signal α_(m2) in accordance with following equations (23)-(25), and provides the calculated signals:

α_(m2) =T _(m2) /J _(m3)   (23)

ω_(m2) =T _(m2)/(s×J _(m3))   (24)

θ_(m2) =T _(m2)/(s ² ×J _(m3))   (25)

[0154] Since second simulation controller 9 a performs the control using first simulation acceleration signal α_(m1), first simulation position signal θ_(m1), first simulation speed signal ω_(m1), second simulation position signal θ_(m2) and second simulation speed signal ω_(m2), the motor controller according to this embodiment can bring the response characteristics of second simulation position signal θ_(m2) and second simulation speed signal ω_(m2) close to the response characteristics of first simulation position signal θ_(m1) and first simulation speed signal ω_(m1) without increasing the values of gains K₃, K₄ to such an extent that the motor controller would lose the stability in the control.

[0155] Also, the motor controller according to this embodiment can provide smoother response characteristics of second simulation position signal θ_(m2), second simulation speed signal ω_(m2) and second simulation acceleration signal α_(m2), as compared with the response characteristics of first simulation acceleration signal α_(m1), first simulation position signal θ_(m1) and first simulation speed signal ω_(m1).

[0156] Further, when machine system 6 is a rigid body system, the motor controller according to this embodiment can operate machine system 6 in accordance with commanded rotation angle signal θ_(ref) by building second numerical model 9 b with a rigid body model.

[0157] As described above, the motor controller according to this embodiment can readily provide appropriate second simulation position signal θ_(m2), second simulation speed signal ω_(m2), second simulation acceleration signal α_(m2), and simulation torque signal T in accordance with the speed and smoothness of required response characteristics by forming second simulation control unit 19 of second simulation controller 9 a and second numerical model 9 b.

[0158] Sixteenth Embodiment

[0159] Next, detailed description will be made on a motor controller according to a sixteenth embodiment of the present invention.

[0160] The motor controller according to this embodiment differs from the motor controller according to the fifteenth embodiment in that second simulation control unit 29 is provided instead of second simulation control unit 19 of FIG. 16.

[0161]FIG. 17 is a block diagram illustrating the configuration of second simulation control unit 29. As illustrated in FIG. 17, second simulation control unit 29 differs from second simulation control unit 19 in that second simulation controller 9 c is provided instead of second simulation controller 9 a.

[0162] Second simulation controller 9 c receives first simulation position signal θ_(m1), first simulation speed signal ω_(m1), first simulation acceleration signal α_(m1), second simulation position signal θ_(m2), second simulation speed signal ω_(m2), and second simulation acceleration signal α_(m2), and calculates second simulation torque signal T_(m2) in accordance with following equation (26), and provides the calculated signal:

T _(m2) =J _(m2)×α_(m1) −J _(m4)×α_(m2) +J _(m3) ×{K ₃(θ_(m1)−θ_(m2))−K₄(ω_(m1)−ω_(m2))}  (26)

[0163] The motor controller according to this embodiment can reduce the amount of overshoot of second simulation speed signal ω_(m2), as compared with second simulation controller 9 a of FIG. 16, by feeding second simulation acceleration signal α_(m2) back to second simulation controller 9 c.

[0164] Seventeenth Embodiment

[0165] Next, detailed description will be made on a motor controller according to a seventeenth embodiment of the present invention.

[0166] The motor controller according to this embodiment employs second numerical model 179 b which is another embodiment of second numerical model 9 b in the motor controllers according to the fifteenth and sixteenth embodiments.

[0167]FIG. 18 is a block diagram illustrating second numerical model 179 b in the motor controller according to this embodiment. As illustrated in FIG. 18, second numerical model 179 b comprises coefficient multiplier 9 b 1, integrator 9 b 2, and integrator 9 b 3.

[0168] Coefficient multiplier 9 b 1 multiplies second simulation torque signal T_(m2) by a coefficient to provide second simulation acceleration signal α_(m2). Integrator 9 b 2 integrates second simulation acceleration signal α_(m2) to provide second simulation speed signal ω_(m2). Integrator 9 b 3 integrates second simulation speed signal ω_(m2) to provide second simulation position signal θ_(m2).

[0169] By fixing second numerical model 179 b to a rigid body mode, the motor controller according to this embodiment can further reduce an error between actual position signal θ and commanded rotation angle signal θ_(ref) of machine system 6, and simultaneously reduce high frequency components included in actual torque command T when machine system 6 is a rigid body system.

[0170] Eighteenth Embodiment

[0171] Next, detailed description will made on a motor controller according to an eighteenth embodiment of the present invention.

[0172] The motor controller according to this embodiment employs second simulation controller 19 a which is another embodiment of second simulation controller 9 a in the motor controller according to the fifteenth embodiment.

[0173]FIG. 19 is a block diagram illustrating the configuration of second simulation controller 19 a. As illustrated in FIG. 19, second simulation controller 19 a comprises subtractor 9 a 1, second simulation position control unit 9 a 2, subtractor 9 a 3, second simulation speed control unit 9 a 6, coefficient multiplier 9 a 5, and adder 9 a 4.

[0174] Subtractor 9 a 1 subtracts second simulation position signal θ_(m2) from first simulation position signal θ_(m1) to provide seventeenth simulation signal SI17. Second simulation position control unit 9 a 2 multiplies seventeenth simulation signal SI17 by K_(P2) as expressed by the following equation (27), and provides the product as eighteenth simulation signal SI18:

SI 18=K _(P2) ×SI 17   (27)

[0175] where K_(P2) is a position proportional control gain of second simulation position control unit 9 a 2.

[0176] Adder/subtractor 9 a 3 subtracts second simulation speed signal ω_(m2) from the sum of eighteenth simulation signal SI18 and first simulation speed signal ω_(m1), and provides the difference signal as nineteenth simulation signal SI19.

[0177] Second simulation speed control unit 9 a 6 multiplies nineteenth simulation signal SI19 by K_(V2) as expressed by the following equation (28) to provide twentieth simulation signal SI20:

SI 20=K _(V2) ×SI 19   (28)

[0178] where K_(V2) is a speed proportional control gain of second simulation speed control unit 9 a 6.

[0179] Coefficient multiplier 9 a 5 receives first simulation acceleration signal α_(m1), calculates twenty first simulation signal SI21 in accordance with the following equation (29), and provides the calculated signal:

SI 21=J _(m2)×α_(m1)   (29)

[0180] Adder 9 a 4 adds twentieth simulation signal SI20 and twenty first simulation signal SI21 to provide second simulation torque signal T_(m2).

[0181] In the motor controller according to this embodiment, second simulation controller 19 a can be readily implemented by an electric circuit or the like by separating the control operations expressed by the aforementioned equations (22) or (26) and the like into second simulation position control unit 9 a 2, second simulation speed control unit 9 a 6 and coefficient multiplier 9 a 5.

[0182] The motor controller according to this embodiment can set each gain of second simulation position control unit 9 a 2 to a small value to readily maintain the stability of the motor controller by separating the operation for generating twentieth simulation signal SI20 into second simulation position control unit 9 a 2 and second simulation speed control unit 9 a 6.

[0183] Nineteenth Embodiment

[0184] Next, detailed description will be made on a motor controller according to a nineteenth embodiment of the present invention.

[0185] The motor controller according to this embodiment employs second simulation controller 29 awhich is another embodiment of second simulation controller 9 a in the motor controller according to the fifteenth embodiment.

[0186]FIG. 20 is a block diagram illustrating the configuration of second simulation controller 29 a. As illustrated in FIG. 20, second simulation controller 29 a comprises extra differentiator 9 a 7, subtractor 9 a 8, and second simulation acceleration control unit 9 a 9 in addition to the components in second simulation controller 19 a of FIG. 19.

[0187] Differentiator 9 a 7 differentiates second simulation speed signal ω_(m2) to provide twenty second simulation signal SI22. Subtractor 9 a 8 subtracts twenty second simulation signal SI22 from first simulation acceleration signal α_(m1) to provide twenty third simulation signal SI23. Second simulation acceleration control unit 9 a 9 receives twenty third simulation signal SI23, calculates twenty fourth simulation signal SI24 in accordance with the following equation (30), and provides the calculated signal:

SI 24=K _(a2) ×SI 23   (30)

[0188] where K_(a2) is an acceleration proportional control gain.

[0189] Twenty fourth simulation signal SI24 is added to the sum of twentieth simulation signal SI20 and twenty first simulation signal SI21 by adder 9 a 4 to generate second simulation torque signal T_(m2).

[0190] With the introduction of second simulation acceleration control unit 9 a 9, the motor controller according to this embodiment can bring the response characteristic of second simulation acceleration signal α_(m2) closer to the response characteristic of first simulation acceleration signal α_(m1), and more rapidly ascend second simulation position signal θ_(m2) and second simulation speed signal ω_(m2).

[0191] Twentieth Embodiment

[0192] Next, detailed description will be made on a motor controller according to a twentieth embodiment of the present invention.

[0193] The motor controller according to this embodiment employs second simulation controller 19 c as another embodiment of second simulation controller 9 c in the motor controller according to the sixteenth embodiment.

[0194]FIG. 21 is a block diagram illustrating the configuration of second simulation controller 19 c. As illustrated in FIG. 21, second simulation controller 19 c comprises subtractor 9 a 1, second simulation position control unit 9 a 2, adder/subtractor 9 a 3, adder 9 a 4, coefficient multiplier 9 a 5, and second simulation speed control unit 9 a 6, similar to second simulation controller 19 a of FIG. 19, and additionally comprises subtractor 9 c 7 and second simulation position control unit 9 c 2.

[0195] Subtractor 9 c 7 subtracts first simulation acceleration signal α_(m1) from second simulation acceleration signal α_(m2) to provide twenty fifth simulation signal SI25. Second simulation acceleration control unit 9 c 8 multiplies twenty fifth simulation signal SI25 by a coefficient to provide twenty sixth simulation signal SI26. Twenty first simulation signal SI21 is applied to adder 9 a 4 which adds it to twenty sixth simulation signal SI26 and twentieth simulation signal SI20 to provide second simulation torque signal T_(m2).

[0196] The motor controller according to this embodiment can set a smaller value to control gain K_(P2) of second simulation position control unit 9 a 2 than in an exclusive position control by separating the operation for generating the twentieth simulation signal SI20 into second simulation position control unit 9 a 2 and second simulation speed control unit 9 a 6.

[0197] Twenty First Embodiment

[0198] Next, detailed description will be made on the configuration of a motor controller according to a twenty first embodiment of the present invention. The motor controller according to this embodiment differs from the motor controller according to the fifteenth embodiment in that second simulation control unit 39 is provided instead of providing second simulation control unit 19 of FIG. 16. FIG. 22 is a block diagram illustrating the configuration of second simulation control unit 39. As illustrated in FIG. 22, second simulation control unit 39 comprises second numerical model 9 e and second simulation controller 9 d.

[0199] Second simulation controller 9 d receives first simulation position signal θ_(m1), first simulation speed signal ω_(m1), first simulation acceleration signal α_(m1), second simulation position signal θ_(m2), second simulation speed signal ω_(m2), second simulation acceleration signal α_(m2), third simulation position signal θ_(L2), and third simulation speed signal ω_(L2), and calculates second simulation torque signal T_(m2) in accordance with following equation (31), and provides second simulation torque signal T_(m2):

T _(m2) =J _(m2)×α_(m1) −J _(m4)×α_(m2) +J _(m3) ×{K ₃(θ_(m1)−θ_(m2))−K ₄(ω_(m1)−ω_(m2))}−K ₅×θ_(L2) −K ₆×ω_(L2)   (31)

[0200] Second numerical model 9e receives second simulation torque signal T_(m2), and solves the following equations (32)-(37) to provide second simulation acceleration signal α_(m2), second simulation speed signal ω_(m2), second simulation position signal θ_(m2), third simulation position signal θ_(L2), and third simulation speed signal ω_(L2):

α_(m2)=(T _(m2) −Tk)/(J _(m5))   (32)

ω_(m2)=(T _(m2) −Tk)/(J _(m5) ×s)   (33)

θ_(m2)=(T _(m2) −Tk)/(J _(m5) ×s ²)   (34)

θ_(L2) =Tk/(J _(m6) ×s ²)   (35)

θ_(L2) =Tk/(J _(m6) ×s)   (36)

Tk=Kc×(θ_(m2)−θ_(L2))   (37)

[0201] where J_(m5), J_(m6) are inertia, Kc is a control gain, and Tk is a simulation torsional torque signal.

[0202] Second simulation controller 9 d performs a feedback control using third simulation position signal θ_(L2) and third simulation speed signal ω_(L2) fed back from second numerical model 9 e which models a two-inertia system, so that the motor controller according to this embodiment can generate appropriate second simulation torque signal T_(m2), second simulation acceleration signal α_(m2), second simulation speed signal ω_(m2), and second simulation angle signal θ_(m2) even when machine system 6 is a two-inertia system.

[0203] Twenty Second Embodiment

[0204] Next, detailed description will be made on a motor controller according to a twenty second embodiment of the present invention. The motor controller according to this embodiment employs second simulation controller 19 d instead of second simulation controller 9 d used in the motor controller according to the twenty first embodiment. FIG. 23 is a block diagram illustrating the configuration of second simulation controller 19 d. As illustrated in FIG. 23, second simulation controller 9 d comprises subtractor 9 d 1, second simulation position controller 9 d 2, adder/subtractor 9 d 3, adder 9 d 4, coefficient multiplier 9 d 5, second simulation speed control unit 9 d 6, subtractor 9 d 7, subtractor 9 d 9, second simulation torsional position compensator 9 d 10, second simulation torsional speed compensator 9 d 8.

[0205] Subtractor 9 d 1 subtracts third simulation speed signal ω_(L2) from first simulation position signal θ_(m1) to provide twenty seventh simulation signal SI27. Second simulation position control unit 9 d 2 provides twenty eighth simulation signal SI28 based on twenty seventh simulation signal SI27. FIG. 24 illustrates the configuration of second simulation position control unit 9 d 2. Second simulation position control unit 9 d 2 comprises coefficient multiplier 9 d 2 a. Coefficient multiplier 9 d 2 a multiplies twenty seventh simulation signal SI27 by K_(P2) to provide twenty eighth simulation signal SI28.

[0206] Adder/subtractor 9 d 3 subtracts third simulation speed signal ω_(L2) from the sum of twenty eighth simulation signal SI28 and first simulation speed signal ω_(m1) to provide twenty ninth simulation signal SI29. Second simulation speed control unit 9 d 6 provides thirtieth simulation signal SI30 based on twenty ninth simulation signal SI29. FIG. 25 illustrates the configuration of second simulation speed control unit 9 d 6. Second simulation position control unit 9 d 6 comprises coefficient multiplier 9 d 6 a. Coefficient multiplier 9 d 6 a multiplies twenty ninth simulation signal SI29 by a coefficient to provide thirtieth simulation signal SI30.

[0207] Subtractor 9 d 9 subtracts the aforementioned third simulation position signal θ_(L2) from second simulation position signal θ_(m2) to provide thirty first simulation signal SI31.

[0208] Second simulation torsional position compensator 9 d 10 provides thirty second simulation signal SI32 based on thirty first simulation signal SI31. FIG. 26 illustrates the configuration of second simulation torsional position compensator 9 d 10. Second simulation torsional position compensator 9 d 10 comprises coefficient multiplier 9 d 10 a. Coefficient multiplier 9 d 10 a calculates thirty second simulation signal SI32 in accordance with the following equation (38), and provides the calculated signal:

SI 32=K _(P3) ×SI 31   (38)

[0209] where K_(P3) is a position proportional control gain.

[0210] Subtractor 9 d 7 subtracts the aforementioned third simulation speed signal ω_(L2) from second simulation speed signal ω_(m2) to provide thirty third simulation signal SI33.

[0211] Second simulation torsional speed compensator 9 d 8 receives thirty third simulation signal SI33 to provide thirty fourth simulation signal SI34. FIG. 27 illustrates the configuration of second simulation torsional speed compensator 9 d 8. Second simulation torsional speed compensator 9 d 8 comprises coefficient multiplier 9 d 8 a. Coefficient multiplier 9 d 8 a calculates thirty fourth simulation signal SI34 from thirty third simulation signal SI33 in accordance with the following equation (39) and provides thirty fourth simulation signal SI34:

SI 34=K _(v3) ×SI 33   (39)

[0212] where K_(V3) is speed proportional control gain.

[0213] Coefficient multiplier 9 d 5 multiplies first simulation acceleration signal α_(m1) by a coefficient to provide thirty fifth simulation signal SI35. Adder 9 d 4 adds thirtieth simulation signal SI30, thirty second simulation signal SI32, thirty fourth simulation signal SI34 and thirty fifth simulation signal SI35 to provide second simulation torque signal T_(m2).

[0214] With the addition of second simulation torsional position compensator 9 d 10 and second simulation torsional speed compensator 9 d 8, the motor controller according to this embodiment can generate appropriate second simulation torque signal T_(m2) even when machine system 6 is a two-inertia system.

[0215] Also, the motor controller according to this embodiment can set a smaller value to control gain K_(P2) of second simulation position control unit 9 d 2 than in an exclusive position control by separating the operation for generating the twentieth simulation signal SI30 into second simulation position control unit 9 d 2 and second simulation speed control unit 9 d 6.

[0216] Twenty Third Embodiment

[0217] Next, detailed description will be made on a motor controller according to twenty third embodiment of the present invention.

[0218] The motor controller according to this embodiment employs second simulation controller 29 d which is another embodiment of second simulation controller 9 d in the motor controller according to the twenty second embodiment.

[0219]FIG. 28 is a block diagram illustrating the configuration of second simulation controller 29 d. As illustrated in FIG. 28, second simulation controller 29 d comprises extra differentiator 9 d 11, subtractor 9 d 12, and second simulation acceleration control unit 9 d 13 in addition to the components in second simulation controller 19 d of FIG. 23.

[0220] Differentiator 9 d 11 differentiates third simulation speed signal ω_(L2) to provide thirty sixth simulation signal SI36. Subtractor 9 d 12 subtracts thirty sixth simulation signal SI36 from first simulation acceleration signal α_(m1) to provide thirty seventh simulation signal SI37.

[0221] Second simulation acceleration control unit 9 d 13 receives thirty seventh simulation signal SI37, calculates thirty eighth simulation signal SI38 in accordance with the following equation (40), and provides the calculated signal:

SI 38=K _(a3) ×SI 37   (40)

[0222] where K_(a3) is an acceleration proportional control gain.

[0223] Adder 9 d 4 adds thirtieth simulation signal SI30, thirty second simulation signal SI30, thirty fourth simulation signal SI34, thirty fifth simulation signal SI35 and thirty eighth simulation signal SI38 to provide second simulation torque signal T_(m2).

[0224] With the addition of second simulation acceleration control unit 9 d 13, the motor controller according to this embodiment can generate appropriate second simulation torque signal T_(m2) such that third simulation speed signal ω_(L2) can have the response characteristic close to that of first simulation speed signal ω_(m1) to readily speed up the control response of machine system 6, even when machine system 6 is a two-inertia system.

[0225] Twenty Fourth Embodiment

[0226] Next, detailed description will be made on a motor controller according to a twenty fourth embodiment of the present invention.

[0227] The motor controller according to this embodiment employs second numerical model 19 e instead of second numerical model 9 e used in the motor controller according to the twenty first embodiment. FIG. 29 is a block diagram illustrating the configuration of second numerical model 19 e. As illustrated in FIG. 29, second numerical model 19 e comprises first inertia system numerical model 9 e 1, spring numerical model 9 e 2, and second inertia system numerical model 9 e 3.

[0228] First inertia system numerical model 9 e 1 receives second simulation torque signal T_(m2), calculates second simulation position signal θ_(m2), second simulation speed signal ω_(m2), and second simulation acceleration signal α_(m2) in accordance with the following equations (41)-(43), and provides the calculated signals:

α_(m2)=(T _(m2) −Tk)/(J _(m5))   (41)

ω_(m2)=α_(m2) /s   (42)

θ_(m2)=ω_(m2) /s   (43)

[0229] Spring numerical model 9 e 2, which has the configuration as in FIG. 30, receives second simulation position signal θ_(m2) and third simulation position signal θ_(L2), and solves the following equation (44) to provide simulation torsional torque signal Tk:

Tk=Kc×(θ_(m2)−θ_(L2))   (44)

[0230] Second inertia system numerical model 9 e 3 calculates third simulation position signal θ_(L2) and third simulation speed signal ω_(L2) in accordance with the following equations (45), (46) based on simulation torsional torque signal Tk, and provides the calculated signals:

ω_(L2) =Tk/(J _(m6) ×s)   (45)

θ_(L2)=ω_(L2) /s   (46)

[0231] In addition, first inertia system numerical model 9 e 1 may impose limitations to second simulation torque signal T_(m2) as following equation (47):

T _(m2) =Tmax (T _(m2) ≧Tmax)

T _(m2) =−Tmax (T _(m2) −<Tmax)   (47)

[0232] where Tmax is a maximum torque of the electric motor.

[0233] By doing so, the motor controller according to this embodiment an generate more appropriate second simulation torque signal T_(m2).

[0234] As described above, the motor controller according to this embodiment can achieve a response of the second numerical model similar to the response of machine system 6 by forming the second numerical model of the two inertia system models and spring numerical model, and can reduce high frequency components included in torque command T, when machine system 6 can be approximated by a two-inertia spring vibration system.

[0235] Twenty Fifth Embodiment

[0236] Next, detailed description will be made on a motor controller according to a twenty fifth embodiment of the present invention.

[0237] This embodiment illustrates an embodiment of actual control means in the motor controller according to the present invention, and in the motor controllers according to this embodiment and twenty sixth and twenty seventh embodiments, those illustrated in the first through twenty fourth embodiments are applied to the first simulation control means, second simulation control means, and the like.

[0238]FIG. 31 is a block diagram illustrating the configuration of actual control unit 10 in the motor controller according to this embodiment. As illustrated in FIG. 31, actual control unit 10 comprises subtractor 10 a, actual position control unit 10 b, differentiator 10 d, subtractor 10 c, actual speed control unit 10 f, differentiator 10 e, subtractor 10 g, first actual acceleration control unit 10 h, and adder 10 i.

[0239] Subtractor 10 a subtracts actual rotation angle signal θ from second simulation position signal θ_(m2), and provides the difference value as thirty ninth simulation signal SI39. Actual position control unit 10 b receives thirty ninth simulation signal SI39, performs a position control, and provides fortieth simulation signal SI40.

[0240] Differentiator 10 d provides forty third simulation signal SI43 based on actual rotation angle signal θ. Adder/subtractor 10 c subtracts forty third simulation signal SI43 from the sum of second simulation speed signal ω_(m2) and fortieth simulation signal SI40 to generate and provide forty first simulation signal SI41. Actual speed control unit 10 f differentiates forty first simulation signal SI41, and provides the differentiated signal as forty second simulation signal SI42.

[0241] Differentiator 10 e differentiates forty third simulation signal SI43, and provides the differentiated signal as forty fourth simulation signal SI44. Subtractor 10 g subtracts forty fourth simulation signal SI44 from second simulation acceleration signal α_(m2), and provides the difference value as forty fifth simulation signal SI45.

[0242] First actual acceleration control unit 10 h receives forty fifth simulation signal SI45, and solves the following equation (48) to provide forty sixth simulation signal SI46:

SI 46=K _(a) ×SI 45   (48)

[0243] where K_(a) is an acceleration proportional control gain.

[0244] Adder 10 i adds forty second simulation signal SI42, forty sixth simulation signal SI46 and second simulation torque signal T_(m2) to provide the sum value as torque command T.

[0245] In the motor controller according to this embodiment, actual rotation angle signal can also have the characteristic close to second simulation position signal θ_(m2) with the addition of first actual acceleration control unit 10 h, even if a slight model error exists between second numerical model and machine system 6.

[0246] The motor controller according to this embodiment can further reduce an error in response between machine system 6 and second numerical model with the addition of first actual acceleration controller to actual control unit 10.

[0247] Twenty Sixth Embodiment

[0248] Next, detailed description will be made on a twenty sixth embodiment of the present invention.

[0249]FIG. 32 is a block diagram illustrating the configuration of actual controller 11 in the motor controller according to this embodiment. As illustrated in FIG. 32, actual controller 11 comprises filter 10 j in addition to the configuration of actual control unit 10 in FIG. 31. Filter 10 j receives actual rotation angle signal θ, and solves the following equation (49) to provide forty seventh simulation signal SI47 which is applied to subtractor 10 a and differentiator 10 d:

SI 47=θ/(T ₄ ×s+1)   (49)

[0250] where T₄ is a time constant.

[0251] With the inclusion of filter 10 j, the motor controller according to this embodiment can reduce a deleterious effect on the response characteristic of actual torque signal T resulting from noise and quantizing error included in actual rotation angle signal θ.

[0252] Twenty Seventh Embodiment

[0253] Next, detailed description will be made on a motor controller according to a twenty seventh embodiment of the present invention. FIG. 33 is a block diagram illustrating the configuration of actual control unit 12. As illustrated in FIG. 33, actual control unit 12 has pseudo differentiator 10 k which is inserted in place of differentiator 10 d in actual control unit 10 of FIG. 31. Pseudo differentiator 10 k receives actual rotation angle signal θ, and solves the following equation (50) to provide forty third simulation signal SI43:

SI 43=θ/(T ₅ ×s+1)   (50)

[0254] where T₅ is a time constant.

[0255] Generally, the level of noise included in actual rotation angle signal θ is smaller than the level of noise included in a differentiated actual rotation angle signal θ, so that the noise included in actual rotation angle signal θ merely exerts an inappreciable deleterious effect on actual torque signal T. Rather, actual rotation angle signal θ often suffers from a delay in phase by filtering actual rotation angle signal θ, resulting in a serious exacerbation of the response characteristic of actual torque signal T.

[0256] Thus, in the motor controller according to this embodiment, actual rotation angle signal θ is applied to actual position control unit 10 b without filtering, while differentiated actual rotation angle signal θ alone is filtered, thereby making it possible to reduce a deleterious effect on the response characteristic of actual torque signal T due to the noise and quantizing error included in differentiated actual rotation angle signal θ and to prevent a phase delay of actual rotation angle signal θ caused by the filtering.

[0257] Consequently, the motor controller according to this embodiment can improve the phase characteristic of position control without applying manipulations to the actual position signal.

[0258] In the motor controllers according to the first through twenty seventh embodiments, the actual control unit, first simulation control unit and second simulation control unit may be comprised of a plurality of processors, wherein respective operations thereof may be implemented by software which runs on these processors. The motor controller according to each embodiment, when comprising a plurality of processors, can largely reduce a control processing time.

[0259] Twenty Eighth Embodiment

[0260] As described above, the motor controllers according to the first through twenty seventh embodiments each comprise two components: the first simulation control unit and second simulation control unit as feed forward control means for applying a command to the actual control unit which performs a feedback control. By doing so, the overall feed forward control means can be designed to meet the requirements for the high-speed property and high stability of a control response by setting a control parameter of the first simulation control unit to improve the high-speed property of the control response and setting a control parameter of the second simulation control unit to increase the stability of the control response.

[0261] However, the motor controllers according to the first through twenty seventh embodiments each imply a problem of a long actual settlement time required for electric motor 3 due to a delay of second simulation position signal θ_(m2) with respect to commanded rotation angle signal θ_(ref). In this regard, the following description will be made on motor controllers according to a twenty eighth through a thirtieth embodiment of the present invention for solving the problem.

[0262] Described first will be a motor controller according to the twenty eighth embodiment of the present invention in detail. FIG. 34 is a block diagram illustrating the configuration of the motor controller according to this embodiment. As illustrated in FIG. 34, the motor controller according to this embodiment differs in configuration from the motor controller of FIG. 2 in that first simulation control unit 68, second simulation control unit 49, and actual control unit 13 are provided instead of first simulation control unit 8, second simulation control unit 9, and actual control unit 10.

[0263] First simulation control unit 68 calculates first simulation speed signal ω_(m1) and first simulation torque signal T_(m1) based on commanded rotation angle signal θ_(ref) provided from command generator 7 and a first control parameter, and provides the calculated signals. First simulation control unit 68 calculates first simulation speed signal ω_(m1) and second simulation torque signal T_(m1) as expressed by the following equations (51), (52):

ω_(m1) =s(T ₁ ×s+1)²×θ_(ref)   (51)

T _(m1) =J×s ²/(T ₁ s+1)²×θ_(ref)   (52)

[0264] where T₁ is a time constant which is the first control parameter, s is a differential operator, and J is the inertia of machine system 6.

[0265] Second simulation control unit 49 performs a proportional control based on a deviation of second simulation position signal θ_(m2) from commanded rotation angle signal θ_(ref) to derive a value, performs an integral control based on a deviation of second simulation position signal θ_(m2) from commanded rotation angle signal θ_(ref) to derive a value, performs a proportional control based on a deviation of first simulation speed signal ω_(m1) from second simulation speed signal ω_(m2), adds these values and first simulation torque signal T_(m1), and provides the sum as second simulation torque signal T_(m2). In addition, second simulation control unit 49 integrates second simulation torque signal T_(m2) once and provides the integrated value as second simulation speed signal ω_(m2), and integrates second simulation speed signal ω_(m2) once and provides the integrated value as second simulation position signal θ_(m2), Specifically, second simulation control unit 49 calculates second simulation position signal θ_(m2), second simulation speed signal ω_(m2) and second simulation torque signal T_(m2) as expressed by the following equations (53)-(55):

θ_(m2)=ω_(m2) /s   (53)

θ_(m2) =T _(m2) /s   (54)

T _(m2) =K _(P)×(θ_(ref)−θ_(m2))+K _(V)×(ω_(m1)−ω_(m2))+T _(m1) +K _(I)×(θ_(ref)−θ_(m2) /s   (55)

[0266] where K_(P) is a first proportional gain, K_(V) is a second proportional gain, K_(I) is an integral gain, and s is a differential operator.

[0267]FIG. 35 is a graph showing the result of a simulation in the motor controller according to this embodiment. FIG. 35 shows manners of transitions in commanded rotation angle signal θ_(ref) second simulation position signal θ_(m2) in the motor controller according to this embodiment, and second simulation position signal θ_(m2) in the motor controller of FIG. 2.

[0268] As shown in FIG. 35, it can be appreciated that second simulation position signal θ_(m2) in the motor controller according to this embodiment follows commanded rotation angle signal θ_(ref) substantially without delay, though presenting slight oscillations after commanded rotation angle signal θ_(ref) reaches one, whereas second simulation position signal θ_(m2) in the motor controller of FIG. 2 delays from commanded rotation angle signal θ_(ref).

[0269] As described above, since second simulation control unit 49 performs the position control based on commanded rotation angle signal θ_(ref) and second simulation position signal θ_(m2) the motor controller according to this embodiment can reduce an actual settlement time of electric motor 3 because a delay in second simulation position signal θ_(m2) can be reduced with respect to commanded rotation angle signal θ_(ref).

[0270] Twenty Ninth Embodiment

[0271] Next, description will be made on a motor controller according to a twenty ninth embodiment of the present invention. FIG. 36 is a block diagram illustrating the configuration of the motor controller according to this embodiment. As illustrated in FIG. 36, the motor controller according to this embodiment differs from the motor controller of FIG. 34 in that signal switch 31 is additionally provided. Also, command generator 17 provides command completion signal S together with commanded rotation angle signal θ_(ref). Command completion signal S takes a first value when commanded rotation angle signal θ_(ref) is provided, i.e., when commanded rotation angle signal θ_(ref) is fluctuating, takes a second value when commanded rotation angle signal θ_(ref) has just been provided, i.e., when commanded rotation angle signal θ_(ref) stops fluctuating, and takes a third value when commanded rotation angle signal θ_(ref) is not provided, i.e., when commanded rotation angle signal θ_(ref) is not fluctuating. The first value is a value which satisfies S<0, the second value is zero, and the third value is a value which satisfies S>0.

[0272] Signal switch 31 applies second simulation control unit 59 with first simulation speed signal ω_(m1) and first simulation torque signal T_(m1), provided from first simulation control unit 68, as they are when command completion signal S takes the first value (for example, S=−1), while sets zero to the value of first simulation speed signal ω_(m1) and the value of first simulation torque signal T_(m1) applied to second simulation control unit 59 when command completion signal S takes the second value (S=0) or third value (for example, S=1).

[0273] Second simulation control unit 59 receives command completion signal S, and calculates second simulation position signal θ_(m2), second simulation speed signal ω_(m2) and second simulation torque signal T_(m2) using the aforementioned equations (53)-(55) to provide the calculated values when command completion signal S takes the first value (S<0) or second value (S>0). However, when command completion signal S takes the second value, i.e., zero, second simulation control unit 59 substitutes zero into the term “K_(I×(θ) _(ref)−θ_(m2))/s” in equation (55) and calculates second simulation torque signal T_(m2).

[0274] Since second simulation control unit 49 performs the position control based on a deviation of second simulation position signal θ_(m2) from commanded rotation angle signal θ_(ref), the motor controller according to this embodiment can reduce an actual settlement time of electric motor 3 because a delay in second simulation position signal θ_(m2) can be reduced with respect to commanded rotation angle signal θ_(ref).

[0275] Further, the motor controller according to this embodiment clears the output of the integrator in the position control, which would cause oscillations and overshooting of second simulation position signal θ_(m2) when commanded rotation angle signal θ_(ref) stops fluctuating, and clears the output of the speed control and first simulation torque signal T_(m1) when commanded rotation angle signal θ_(ref) is not fluctuating. Consequently, the motor controller according to this embodiment can limit overshooting and oscillations of second simulation position signal θ_(m2) which could occur when commanded rotation angle signal θ_(ref) stops fluctuating.

[0276]FIG. 37 is a graph showing the result of a simulation in the motor controller according to this embodiment. FIG. 37 shows manners of fluctuations in commanded rotation angle signal θ_(ref), second simulation position signal θ_(m2) in this embodiment, and second simulation position signal θ_(m2) in the motor controller of FIG. 2.

[0277] As shown in FIG. 37, second simulation position signal θ_(m2) in the motor controller according to this embodiment follows commanded rotation angle signal θ_(ref) substantially without delay, and moreover is free from oscillations after commanded rotation angle signal θ_(ref) reaches one, as appearing on second simulation position signal θ_(m2) of the motor controller according to the twenty eighth embodiment in FIG. 37.

[0278] Thirtieth Embodiment

[0279] Next, description will be made on a motor controller according to a thirtieth embodiment of the present invention. FIG. 38 is a block diagram illustrating the configuration of the motor controller according to this embodiment. As illustrated in FIG. 38, the motor controller according to this embodiment differs from the motor controller of FIG. 36 in that command completion detector 32 is additionally provided.

[0280] Command completion detector 32 receives commanded rotation angle signal θ_(ref) provided from command generator 7, and provides command completion signal S. Command completion detector 32 sets command completion signal S to a first value (S<0, for example, −1) when a differentiated value of commanded rotation angle signal θ_(ref) is non-zero, i.e., when commanded rotation angle signal θ_(ref) is fluctuating. Also, command completion detector 32 sets command completion signal S provided therefrom to a second value (S=0) when a differentiated value of commanded rotation angle signal θ_(ref) is zero and a twice differentiated value of the same is non-zero, i.e., when the commanded rotation angle signal stops fluctuating. Further, command completion detector 32 sets command completion signal S to a third value (S>0, for example, one) when the differentiated value and twice differentiated value of commanded rotation angle signal θ_(ref) are both zero, i.e., when the commanded rotation angle signal is not fluctuating. Signal switch 31 and second simulation control unit 59 receive command completion signal S provided from command completion detector 31 to perform similar operations to those described in the twenty ninth embodiment.

[0281] As described above, the motor controller according to this embodiment, with command completion detector 32 provided therein, can automatically create command completion signal S for limiting overshooting and oscillations occurring in second simulation position signal θ_(m2).

[0282] In the motor controllers according to the twenty eighth through thirtieth embodiments, the actual control unit, first simulation control unit, and second simulation control unit may be comprised of a plurality of processors, wherein their respective operations may be implemented by software which runs on these processors. The motor controller according to each embodiment, when comprising a plurality of processors, can largely reduce a control processing time. The reduced control processing time results in a shorter delay of second simulation position signal θ_(m2) with respect to commanded rotation angle signal θ_(ref) and in reduced overshooting and oscillations occurring in second simulation position signal θ_(m2).

[0283] Description will be made on reference numerals shown in FIGS. 1 through 38.

[0284]1 load mechanism;

[0285]2 transmission mechanism;

[0286]3 electric motor;

[0287]4 power converting circuit;

[0288]5 actual observing unit;

[0289]6 machine system;

[0290]7, 17 command generators;

[0291]8, 28, 38, 48, 58, 68 first simulation control units;

[0292]8 a, 68 a, 78 a, 88 a, 98 a first simulation controllers;

[0293]8 a 1, 8 a 12 first a simulation position control units;

[0294]8 a 1 a subtractor;

[0295]8 a 1 b, 8 a 1 c coefficient multipliers;

[0296]8 a 1 d integrator;

[0297]8 a 1 e adder;

[0298]8 a 2, 8 a 22 first a simulation speed control units;

[0299]8 a 2 a subtractor;

[0300]8 a 2 b, 8 a 2 c coefficient multipliers;

[0301]8 a 2 d integrator;

[0302]8 a 2 e adder;

[0303]8 a3 , 8 a 32 first b simulation position control units;

[0304]8 a 3 a subtractor;

[0305]8 a 3 b, 8 a 3 c coefficient multipliers;

[0306]8 a 3 d integrator;

[0307]8 a 3 e adder;

[0308]8 a 4, 8 a 42 first b simulation speed control units;

[0309]8 a 4 a differentiator;

[0310]8 a 4 b subtractor;

[0311]8 a 4 c, 8 a 4 f coefficient multipliers;

[0312]8 a 4 d integrator;

[0313]8 a 4 e, 8 a 5 adders;

[0314]8 a 6 first a simulation limiter;

[0315]8 a 7 first b simulation limiter;

[0316]8 b, 138 b first a numerical models;

[0317]8 b 1 coefficient multiplier;

[0318]8 b 2, 8 b 3 integrators;

[0319]8 c first command processor;

[0320]8 d first simulation signal processor;

[0321]8 e second simulation signal processor;

[0322]8 f second command processor;

[0323]8 g third simulation signal processor;

[0324]8 h fourth simulation signal processor;

[0325]8 i, 148 i first b numerical models;

[0326]8 i 1 coefficient multiplier;

[0327]8 i 2, 8 i 3 integrators;

[0328]8 j fifth simulation signal processor;

[0329]9, 19, 29, 39, 49, 59 second simulation control units;

[0330]9 a, 29 a 2a-th simulation controllers;

[0331]9 a 1 subtractor;

[0332]9 a 2 second a simulation position control unit;

[0333]9 a 3 subtractor;

[0334]9 a 4 adder;

[0335]9 a 5 coefficient multiplier;

[0336]9 a 6 second a simulation speed control unit;

[0337]9 a 7 differentiator;

[0338]9 a 8 subtractor;

[0339]9 a 9 second a simulation acceleration control unit;

[0340]9 b, 179 b second numerical models;

[0341]9 b 1 coefficient multiplier;

[0342]9 b 2, 9 d 3 integrators;

[0343]9 c, 19 c second b simulation controllers;

[0344]9 c 7 subtractor;

[0345]9 c 8 second b simulation acceleration control unit;

[0346]9 d, 29 d second c simulation controllers;

[0347]9 d 1 subtractor;

[0348]9 d 2 second a simulation position control unit;

[0349]9 d 2 a coefficient multiplier;

[0350]9 d 3 subtractor;

[0351]9 d 4 adder;

[0352]9 d 5 coefficient multiplier;

[0353]9 d 6 second a simulation speed control unit;

[0354]9 d 6 a coefficient multiplier;

[0355]9 d subtractor;

[0356]9 d 8 second a simulation torsional speed compensator;

[0357]9 d 8 a coefficient multiplier;

[0358]9 d 9 subtractor;

[0359]9 d 10 second a simulation torsional position compensator;

[0360]9 d 10 a coefficient multiplier;

[0361]9 d 11 differentiator;

[0362]9 d 12 subtractor;

[0363]9 d 13 second b simulation acceleration control unit;

[0364]9 e, 19 e second b numerical models;

[0365]9 e 1 first inertia numerical model;

[0366]9 e 2 spring numerical model;

[0367]9 e 2 a subtractor;

[0368]9 e 2 b coefficient multiplier;

[0369]9 e 3 second inertia numerical model;

[0370]10, 11, 12, 13 actual control units;

[0371]10 a subtractor;

[0372]10 b actual position control unit;

[0373]10 c subtractor;

[0374]10 d, 10 e differentiators;

[0375]10 f actual speed control unit;

[0376]10 g subtractor;

[0377]10 h first actual acceleration control unit;

[0378]10 i adder;

[0379]10 j filter;

[0380]10 _(k) pseudo differentiator;

[0381]21 motor rotation angle command signal generator circuit;

[0382]22 A control circuit;

[0383]23 B control circuit;

[0384]24 two-inertia-system simulation circuit;

[0385]25 feed forward signal processing circuit;

[0386]31 signal switch;

[0387]32 command completion detector. 

1. A motor controller for controlling a machine system having a power converting circuit which operates to drive an electric motor coupled to a load mechanism through a transmission mechanism in response to a torque command, and actual observing unit which provides an actual rotation angle signal and an actual speed signal of said electric motor, said motor controller characterized by comprising: first simulation control means for calculating a first simulation position signal, a first simulation speed signal and a first simulation acceleration signal based on a commanded rotation angle signal provided from an upper rank apparatus and at least one first control parameter, to provide the calculated signals; second simulation control means for calculating a second simulation position signal, a second simulation speed signal, a second simulation acceleration signal and a simulation torque signal based on said first simulation position signal, said first simulation speed signal, said first simulation acceleration signal and at least one second control parameter to provide the calculated signals; and actual control means for performing a feedback control based on said second simulation position signal, said second simulation speed signal, said second simulation acceleration signal and said simulation torque signal to calculate and provide said torque command.
 2. The motor controller according to claim 1, wherein: said first simulation control means provides an output of a two-stage first-order lag filter having a first time constant which receives said commanded rotation angle signal as said first simulation position signal, provides a differentiated signal of the output of said two-stage first-order lag filter as said first simulation speed signal, and provides a differentiated signal of the output of said two-stage first-order lag filter as said first simulation speed signal; and said second simulation control means provides an output of a first-order lag filter having a second time constant which receives said first simulation position signal as said second simulation position signal, provides an output of a first-order lag filter having the second time constant which receives said first simulation speed signal as said second simulation speed signal, and provides an output of a first-order lag filter having the second time constant which receive said first simulation acceleration signal as said second simulation acceleration signal.
 3. The motor controller according to claim 1, wherein said first simulation control means comprises: a first command processor for providing an output of a two-stage first-order lag filter having a first time constant which receives said commanded rotation angle signal as said first simulation position signal; a first simulation signal processor for providing an integrated signal of said first simulation speed signal as said first simulation position signal; and a second simulation signal processor for providing a differentiated signal of said first simulation speed signal as said first simulation acceleration signal.
 4. The motor controller according to claim 1, wherein said first simulation control means comprises: a second command processor for providing an output of a two-stage first-order lag filter having a first time constant which receives said commanded rotation angle signal as said first simulation position signal; a third simulation signal processor for differentiating said first simulation position signal to provide said first simulation speed signal; and a fourth simulation signal processor for differentiating said first simulation speed signal to provide said first simulation acceleration signal.
 5. The motor controller according to claim 1, wherein: said first simulation control means comprises: a first simulation controller for calculating a first simulation torque signal based on a deviation of said first simulation position signal from said commanded rotation angle signal, and said first simulation speed signal; and a first numerical model for calculating said first simulation acceleration signal, said first simulation speed signal and said first simulation position signal based on said first simulation torque signal.
 6. The motor controller according to claim 5, wherein: said first simulation controller multiplies the deviation of said first simulation position signal from said commanded rotation angle signal by a first control gain to generate a first signal, multiplies said first simulation speed signal by a second control gain to generate a second signal, and multiplies a difference between said first signal and said second signal by a first inertia to provide the product signal as said first simulation torque signal; and said first numerical model subtracts said first inertia from said first simulation torque signal to generate a signal which is provided as said first simulation acceleration signal, integrates said first simulation acceleration signal to generate a signal which is provided as said first simulation speed signal, and integrates said first simulation speed signal to generate a signal which is provided as said first simulation position signal.
 7. The motor controller according to claim 6, wherein said first numerical model comprises: a coefficient multiplier for subtracting an inertia from said first simulation torque signal to provide the difference signal as said first simulation acceleration signal; an integrator for integrating said first simulation acceleration signal to provide the integrated signal as said first simulation speed signal; and an integrator for integrating said first simulation speed signal to provide the integrated signal as said first simulation position signal.
 8. The motor controller according to claim 1, wherein said first simulation control means comprises: a first simulation controller for calculating a first simulation torque signal based on a deviation of said first simulation position signal from said commanded rotation angle signal, and said first simulation speed signal; a first numerical model for calculating said first simulation speed signal and said first simulation position signal based on said first simulation torque signal; and a fifth simulation signal processor for differentiating an output of a first-order filter having a third time constant which receives said first simulation speed signal, to provide the differentiated signal as said first simulation acceleration signal.
 9. The motor controller according to claim 8, wherein: said first simulation controller multiplies the deviation of said first simulation position signal from said commanded rotation angle signal by a first control gain to generate a first signal, multiplies said first simulation speed signal by a second control gain to generate a second signal, and multiplies a difference between said first signal and said second signal by a first inertia to provide the product signal as said first simulation torque signal; and said first numerical model divides said first simulation torque signal bysaid first inertia, integrates the quotient signal to provide the integrated signal as said first simulation speed signal, and integrates said first simulation speed signal to provide the integrated signal as said first simulation position signal.
 10. The motor controller according to claim 9, wherein said first numerical model comprises: a coefficient multiplier for subtracting an inertia from said first simulation torque signal to provide the difference signal as a sixteenth simulation signal; an integrator for integrating said sixteenth simulation signal to provide the integrated signal as said first simulation speed signal; and an integrator for integrating said first simulation speed signal to provide the integrated signal as said first simulation position signal.
 11. The motor controller according to claim 5, wherein said first simulation controller comprises a first simulation position control unit for providing said first simulation speed command signal based on a deviation of the first simulation position signal from said commanded rotation angle signal; and a first simulation speed control unit for providing said first simulation torque signal based on a deviation of said first simulation speed signal from said first simulation speed command signal.
 12. The motor controller according to claim 11, wherein: said first simulation position control unit multiplies a deviation of said first simulation position signal from said commanded rotation angle signal by a first position proportional control gain to provide the product signal as said first simulation speed command signal; and said first simulation speed control unit multiplies the deviation of said first simulation speed signal from said first simulation speed command signal by a first speed proportional control gain to provide the product signal as said first simulation torque signal.
 13. The motor controller according to claim 11, wherein said first simulation position control unit comprises: a subtractor for subtracting said first simulation position signal from said commanded rotation angle signal to provide the difference signal as a first simulation position error signal; a coefficient multiplier for amplifying said first simulation position error signal by a first position proportional control gain to provide the amplified signal as a tenth simulation signal; a coefficient multiplier for amplifying said first simulation position error signal by a first position integral control gain to provide the amplified signal as an eleventh simulation signal; an integrator for integrating said eleventh simulation signal to provide the integrated signal as a twelfth simulation signal; and an adder for adding said tenth simulation signal and said twelfth simulation signal to provide the sum signal as said first simulation speed command signal.
 14. The motor controller according to claim 11 or 13, wherein said first simulation speed control unit comprises: a subtractor for subtracting said first simulation speed signal from said first simulation speed command signal to provide the difference signal as a first simulation speed error signal; a coefficient multiplier for amplifying said first simulation speed error signal by a first speed-proportional control gain to provide the amplified signal as a thirteenth simulation signal; a coefficient multiplier for amplifying said first simulation speed error signal by a first speed integral control gain to provide the amplified signal as a fourteenth simulation signal; an integrator for integrating said fourteenth simulation signal to provide the integrated signal as a fifteenth simulation signal; and an adder for adding said thirteenth simulation signal and said fifteenth simulation signal to provide the sum signal as said first simulation torque command signal.
 15. The motor controller according to claim 5, wherein said first simulation controller comprises: a first simulation position control unit for providing as a first simulation torque command signal based on a deviation of said first simulation position signal from said commanded rotation angle signal; a first simulation speed control unit for providing as a second simulation torque command signal based on a deviation of the first simulation speed signal from the commanded rotation angle signal; and an adder for adding said first simulation torque command signal and said second simulation torque command signal to provide the sum signal as said first simulation torque signal.
 16. The motor controller according to claim 15, wherein: said first simulation position control unit multiplies the deviation of said first simulation position signal from said commanded rotation angle signal by a first position proportional control gain to provide the product signal as said first simulation torque command signal; and said first simulation speed control unit multiplies the deviation of said first simulation speed signal from said commanded rotation angle signal by a first speed proportional control gain to provide the product signal as said second simulation torque command signal.
 17. The motor controller according to claim 15, wherein said first simulation position control unit comprises: a subtractor for subtracting said first simulation position signal from said commanded rotation angle signal to provide the difference value signal as a first simulation position error signal; a coefficient multiplier for amplifying the value of said first simulation position error signal by a first position proportional control gain to provide the amplified signal as a sixteenth simulation signal; a coefficient multiplier for amplifying the value of said first simulation position error signal by a first position integral control gain to provide the amplified signal as a seventeenth simulation signal; an integrator for integrating said seventeenth simulation signal to provide the integrated signal as an eighteenth simulation signal; and an adder for adding said sixteenth simulation signal and said eighteenth simulation signal to provide the sum signal as the first simulation torque command signal.
 18. The motor controller according to claim 15 or 17, wherein said first simulation speed control unit comprises: a differentiator for differentiating said commanded rotation angle signal to provide the differentiated signal as a nineteenth simulation signal; a subtractor for subtracting said nineteenth simulation signal from said first simulation speed signal to provide a first simulation speed error signal; a coefficient multiplier for amplifying said first simulation speed error signal by a first speed integral control gain to provide the amplified signal as a twentieth simulation signal; a coefficient multiplier for amplifying said first simulation speed error signal by a first speed proportional control gain to provide the amplified signal as a twenty first simulation signal; an integrator for integrating said twentieth simulation signal to provide a twenty second simulation signal; and an adder for adding said twenty first simulation signal and said twenty second simulation signal to provide the sum signal as said second simulation torque command signal.
 19. The motor controller according to any of claims 5 through 18, wherein said first simulation controller further comprises a first simulation limiter for limiting the value of said first simulation torque signal such that said first simulation torque signal falls within a predetermined range of said electric motor.
 20. The motor controller according to any of claims 1 and 3 through 19, wherein said second simulation control means comprises: a second simulation controller for calculating said second simulation torque signal based on a deviation of said second simulation position signal from said first simulation position signal, a deviation of said second simulation speed signal from said first simulation speed signal and said first simulation acceleration signal to provide said simulation torque signal; and a second numerical model for calculating said second simulation acceleration signal, said second simulation speed signal and said simulation position signal based on said second simulation torque signal to provide the calculated signals.
 21. The motor controller according to claim 20, wherein: said second simulation controller multiplies the deviation of said second simulation position signal from said first simulation position signal by a third control gain to generate a first signal, multiplies the deviation of said second simulation speed signal from said first simulation speed signal by a fourth control gain to generate a second signal, subtracts said second signal from said first signal and multiplies the difference signal by a third inertia to generate a third signal, multiplies said first simulation acceleration signal by a second inertia to generate a fourth signal, and adds said fourth signal and said third signal to provide the sum signal as said second simulation torque signal; and said second numerical model divides said second simulation torque signal by said third inertia to provide the quotient signal as said second simulation acceleration signal, integrates said second simulation acceleration signal to provide the integrated signal as said second simulation speed signal, and integrates said second simulation speed signal to provide the integrated signal as the second simulation position signal.
 22. The motor controller according to claim 20, wherein said second simulation controller comprises: a subtractor for subtracting said second simulation position signal from said first simulation position signal to provide a seventeenth simulation signal; a second simulation position control unit for amplifying said seventeenth simulation signal by a second position proportional control gain to provide an eighteenth simulation signal; an adder/subtractor for subtracting said second simulation speed signal from the sum of said eighteenth simulation signal and said first simulation speed signal to provide the difference signal as a nineteenth simulation signal; a second simulation speed control unit for amplifying said nineteenth simulation signal by a second speed-proportional control gain to provide a twentieth simulation signal; a coefficient multiplier for multiplying first simulation acceleration signal by a second inertia to provide the product signal as a twenty first simulation signal; and an adder for adding said twentieth simulation signal and said twenty first simulation signal to provide the sum signal as said second simulation torque signal.
 23. The motor controller according to claim 22, wherein said second simulation controller further comprises: a differentiator for differentiating said second simulation speed signal to provide a twenty second simulation signal; a subtractor for subtracting the twenty second simulation signal from said first simulation acceleration signal to provide a twenty third simulation signal; a second simulation acceleration control unit for amplifying said twenty third simulation signal by an acceleration proportional control gain to provide the amplified signal as a twenty fourth simulation signal; and an adder for adding said twenty fourth simulation signal, said twentieth simulation signal and said twenty first simulation signal to provide the sum signal as said second simulation torque signal.
 24. The motor controller according to any of claims 1 and 3 through 19, wherein said second simulation control means comprises: a second simulation controller for calculating said second simulation torque signal based on a deviation of said second simulation position signal from said first simulation position signal, a deviation of said second simulation speed signal from said first simulation speed signal, and a deviation of said second simulation acceleration signal from said first simulation acceleration signal to provide said second simulation torque signal; and a second numerical model for calculating said second simulation acceleration signal, said second simulation speed signal and said second simulation position signal based on said second simulation torque signal to provide the calculated signals.
 25. The motor controller according to claim 22, wherein: said second simulation controller multiplies the deviation of said second simulation position signal from said first simulation position signal by a third control gain to generate a first signal, multiplies the deviation of said second simulation speed signal from said first simulation speed signal by a fourth control gain to generate a second signal, and subtracts said second signal from said first signal and multiplies the difference signal by a third inertia to generate a third signal, multiplies said first simulation acceleration signal by a second inertia to generate a fourth signal, multiplies said second simulation acceleration signal by a fourth inertia to generate a fifth signal, and subtracts said fifth signal from the sum of said fourth signal and said third signal to provide the difference signal as said second simulation torque signal, and said second numerical model divides said second simulation torque signal by said third inertia to provide the quotient signal as said second simulation acceleration signal, integrates said second simulation acceleration signal to provide the integrated signal as said second simulation speed signal, and integrates said second simulation speed signal to provide the integrated signal as said second simulation position signal.
 26. The motor controller according to claim 22, wherein said second simulation controller comprises: a subtractor for subtracting said second simulation position signal from said first simulation position signal to provide a seventeenth simulation signal; a second simulation position control unit for amplifying said seventeenth simulation signal by a second position proportional control gain to provide an eighteenth simulation signal; an adder/subtractor for subtracting said second simulation speed signal from the sum of said eighteenth simulation signal and said first simulation speed signal to provide the difference signal as a nineteenth simulation signal; a second simulation speed control unit for amplifying said nineteenth simulation signal by a second speed proportional control gain to provide a twentieth simulation signal; a coefficient multiplier for multiplying said first simulation acceleration signal by a second inertia to provide the product signal as a twenty first simulation signal; a subtractor for subtracting said first simulation acceleration signal from said second simulation acceleration signal to provide a twenty fifth simulation signal; a second simulation acceleration control unit for amplifying said twenty fifth simulation signal by an acceleration proportional control gain to provide a twenty sixth simulation signal; and an adder for adding said twenty first simulation signal, said twenty sixth simulation signal and said twentieth simulation signal to provide the sum as the second simulation torque signal.
 27. The motor controller according to any of claims 20 through 26, wherein said second numerical model comprises: a coefficient multiplier for multiplying said second simulation torque signal by the inverse of the third inertia to provide said second simulation acceleration signal; an integrator for integrating said second simulation acceleration signal to provide said second simulation speed signal; and an integrator for integrating said second simulation speed signal to provide said second simulation position signal.
 28. The motor controller according to any of claims 1 and 3 through 19, wherein said second simulation control means comprises: a second numerical model for providing said second simulation position signal, said second simulation speed signal, said second simulation acceleration signal, a third simulation position signal and a third simulation speed signal based on said second simulation torque signal; and a second simulation controller for calculating said second simulation torque signal based on said second simulation position signal, said second simulation speed signal, said second simulation acceleration signal, said third simulation position signal and said third simulation speed signal.
 29. The motor controller according to claim 28, wherein: said second simulation controller multiplies a deviation of said second simulation position signal from said first simulation position signal by a third control gain to generate a first signal, multiplies a deviation of said second simulation speed signal from said first simulation speed signal by a fourth control gain to generate a second signal, subtracts said second signal from said first signal and multiplies the difference signal by a third inertia to generate a third signal, multiplies said first simulation acceleration signal by a second inertia to generate a fourth signal, multiplies said second simulation acceleration signal by a fourth inertia to generate a fifth signal, multiplies said third simulation position signal by a fifth control gain to generate a sixth signal, multiplies said third simulation speed signal by a sixth control gain to generate a seventh signal, and subtracts said fifth signal, said sixth signal and said seventh signal from the sum of said fourth signal and said third signal to provide the difference signal as said second simulation torque signal; and said second numerical model receives said second simulation torque signal, multiplies a deviation of said third simulation position signal from said second simulation position signal by a spring constant to generate the product signal as a simulation torsional torque signal, divides said simulation torsional torque signal by a sixth inertia, and integrates the quotient signal to provide the integrated signal as said third simulation speed signal, divides said simulation torsional torque signal by said sixth inertia, and integrates the quotient signal twice to provide the twice integrated signal as said third simulation position signal, divides a deviation of said simulation torsional torque signal from said second simulation torque signal by a fifth inertia to provide the quotient signal as said second simulation acceleration signal, divides a deviation of said simulation torsional torque signal from said second simulation torque signal by said fifth inertia and integrates the quotient signal to provide the integrated signal as said second simulation speed signal, divides the deviation of said simulation torsional torque signal from said second simulation torque signal by said fifth inertia and integrates the quotient signal twice to provide the twice integrated signal as said second simulation position signal.
 30. The motor controller according to claim 28, wherein: said second simulation controller comprises: a subtractor for subtracting said third simulation position signal from said first simulation position signal to provide a twenty seventh simulation signal; a second simulation position control unit for multiplying said twenty seventh simulation signal by a second position proportional control gain to provide the product signal as a twenty eighth simulation signal; an adder/subtractor for subtracting said third simulation speed signal from the sum of said twenty eighth simulation signal and said first simulation speed signal to provide the difference signal as a twenty ninth simulation signal; a second simulation speed control unit for multiplying said twenty ninth simulation signal by a second speed proportional control gain to provide the product signal as a thirtieth simulation signal; a subtractor for subtracting said third simulation position signal from said second simulation position signal to provide the difference signal as a thirty first simulation signal; a second simulation torsional position compensator for multiplying said thirty first simulation signal by a third position proportional control gain to provide the product signal as a thirty second simulation signal; a subtractor for subtracting said third simulation speed signal from said second simulation speed signal to provide the difference signal as a thirty third simulation signal; a second simulation torsional speed compensator for multiplying said thirty third simulation signal by a third speed-proportional control gain to provide the product signal as a thirty fourth simulation signal; a coefficient multiplier for multiplying said first simulation acceleration signal by a second acceleration proportional control gain to provide the product signal as a thirty fifth simulation signal; and an adder for adding said thirtieth simulation signal, said thirty second simulation signal, said thirty fourth simulation signal and said thirty fifth simulation signal to provide the sum signal as said second simulation torque signal.
 31. The motor controller according to claim 30, wherein said second simulation controller further comprises: a differentiator for differentiating said third simulation speed signal to provide a thirty sixth simulation signal; a subtractor for subtracting said thirty sixth simulation signal from said first simulation acceleration signal to provide a thirty seventh simulation signal; a second simulation acceleration control unit for multiplying said thirty seventh signal by a third acceleration proportional control gain to provide the product signal as a thirty eighth simulation signal; and an adder for adding said thirty simulation signal, said thirty second simulation signal, said thirty fourth simulation signal, said thirty fifth simulation signal and said thirty eighth simulation signal to provide the sum signal as said second simulation torque signal.
 32. The motor controller according to any of claims 28 through 31, wherein said second numerical model comprises: a spring numerical model for multiplying the deviation of said third simulation position signal from said second simulation position signal by a spring constant to provide the product signal as a simulation torsional torque signal; a first inertia system numerical model for dividing the deviation of said simulation torsional torque signal from said second simulation torque signal by a fifth inertia to provide the quotient signal as said second simulation acceleration signal, integrating said second simulation acceleration signal to provide the integrated signal as said second simulation speed signal, and integrating said second simulation speed signal to provide the integrated signal as said second simulation position signal; and a second inertia system numerical model for dividing said simulation torsional torque signal by the sixth inertia and integrating the quotient signal to provide the integrated signal as said third simulation speed signal, and integrating said third simulation speed signal to provide the integrated signal as said third simulation position signal.
 33. The motor controller according to any of claims 1 through 32, wherein said actual control means comprises: a subtractor for subtracting said actual rotation angle signal from said second simulation position signal to provide the difference signal as a thirty ninth simulation signal; an actual position controller for receiving said thirty ninth simulation signal to perform a position control to provide a fortieth simulation signal; a differentiator for differentiating said actual rotation angle signal to provide a forty third simulation signal; a subtractor for subtracting said forty third simulation signal from the sum of said second simulation speed signal and said fortieth simulation signal to provide a forty first simulation signal; an actual speed controller for differentiating said forty first simulation signal to provide the differentiated signal as a forty second simulation signal; a differentiator for differentiating said forty third simulation signal to provide the differentiated signal as a forty forth simulation signal; a subtractor for subtracting said forty fourth simulation signal from said second simulation acceleration signal to provide the difference signal as a forty fifth simulation signal; a first actual acceleration controller for receiving said forty fifth simulation signal, and amplifying said forty fifth simulation signal by a first acceleration proportional control gain to provide the amplified signal as a forty sixth simulation signal; and an adder for adding said forty second simulation signal, said forty sixth simulation signal and said second simulation torque signal to provide the sum signal as an actual torque command.
 34. The motor controller according to claim 33, wherein said actual rotation angle signal employed therein passes through a first-order filter having a fourth time constant.
 35. The motor controller according to claim 33, wherein said differentiator for differentiating said actual rotation angle signal to provide a forty third simulation signal is a pseudo differentiator which comprises first-order filter having a fifth time constant.
 36. A motor controller for controlling a machine system having a power converting circuit which operates to drive an electric motor coupled to a load mechanism through a transmission mechanism in response to a torque command, and actual observing unit which provides an actual response signal of said electric motor, said motor controller characterized by comprising: first simulation control means for calculating a first simulation speed signal and a first simulation torque signal based on a commanded rotation angle signal provided from an upper rank apparatus and at least one control parameter to provide said first simulation speed signal and said first simulation torque signal; second simulation control means for performing a proportional control based on a deviation of a second simulation position signal from said commanded rotation angle signal to calculate a value, performing an integral control based on the deviation of said second simulation position signal from said commanded rotation angle signal to calculate a value, performing a proportional control based on a deviation of a second simulation speed signal from said first simulation speed signal to calculate a value, and adding said values and the value of the first simulation torque signal to provide the sum as said second simulation torque signal; integrating said second simulation torque signal once to provide the integrated signal as the second simulation speed signal; and integrating said second simulation speed signal once to provide the integrated signal as the second simulation position signal; and actual control means for performing a feedback control based on said second simulation position signal, said second simulation speed signal and said second simulation torque signal to calculate and provide said torque command.
 37. The motor controller according to claim 36, wherein said second simulation control means receives a command completion signal which takes a first value when said commanded rotation angle signal is fluctuating, takes a second value when said commanded rotation angle signal stops fluctuating, and takes a third value when said commanded rotation angle signal is not fluctuating, for setting zero to the value calculated by performing said integral control when said commanded rotation angle signal takes the second value.
 38. The motor controller according to claim 37, further comprising: a signal switch for applying said second simulation control means with said first simulation speed signal and said first simulation torque signal provided from said first simulation control means as they are when said command completion signal takes said first value; and setting zero to the value of said first simulation speed signal and the value of said first simulation torque signal applied to said second simulation control means when said command completion signal takes said second value or said third value.
 39. The motor controller according to claim 38, further comprising: a command completion detector for setting said first value to the value of said command completion signal when a differentiated value of said commanded rotation angle signal is non-zero; setting said second value to the value of said command completion signal when the differentiated value of said commanded rotation angle signal is zero and a twice differentiated value of the same is non-zero; and setting said third value to the value of said command completion signal when the differentiated value and said twice differentiated value of said commanded rotation angle signal are both zero.
 40. The motor controller according to any of claims 1 through 39, comprising software running on a plurality of processors. 